View source for 6cka


==Crystal Structure of Paratox==
<StructureSection load='6cka' size='340' side='right'caption='[[6cka]], [[Resolution|resolution]] 1.56&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6cka]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptococcus_pyogenes_MGAS315 Streptococcus pyogenes MGAS315]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6CKA OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6CKA FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.559&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=MSE:SELENOMETHIONINE'>MSE</scene></td></tr>
<tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=6cka FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6cka OCA], [https://pdbe.org/6cka PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6cka RCSB], [https://www.ebi.ac.uk/pdbsum/6cka PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6cka ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A0H2UWN8_STRP3 A0A0H2UWN8_STRP3] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Horizontal gene transfer is an important means of bacterial evolution. This includes natural genetic transformation, where bacterial cells become "competent" and DNA is acquired from the extracellular environment. Natural competence in many species of Streptococcus, is regulated by quorum sensing via the ComRS receptor-signal pair. The ComR-XIP (mature ComS peptide) complex induces expression of the alternative sigma factor SigX, which targets RNA polymerase to CIN-box promoters to activate genes involved in DNA uptake and recombination. In addition, the widely distributed Streptococcus prophage gene paratox (prx) also contains a CIN-box, and here we demonstrate it to be transcriptionally activated by XIP. In vitro experiments demonstrate that Prx binds ComR directly and prevents the ComR-XIP complex from interacting with DNA. Mutations of prx in vivo caused increased expression of the late competence gene ssb when induced with XIP as compared to wild-type, and Prx orthologues are able to inhibit ComR activation by XIP in a reporter strain which lacks an endogenous prx. Additionally, an X-ray crystal structure of Prx reveals a unique fold that implies a novel molecular mechanism to inhibit ComR. Overall, our results suggest Prx functions to inhibit the acquisition of new DNA by Streptococcus.

The conserved mosaic prophage protein paratox inhibits the natural competence regulator ComR in Streptococcus.,Mashburn-Warren L, Goodman SD, Federle MJ, Prehna G Sci Rep. 2018 Nov 8;8(1):16535. doi: 10.1038/s41598-018-34816-7. PMID:30409983<ref>PMID:30409983</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6cka" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptococcus pyogenes MGAS315]]
[[Category: Prehna G]]